Merge pull request #795 from tahnok/python3-build-sh

Use python3 not python in build.sh

Author: liamcottle

build.sh

@@ -60,7 +60,7 @@ build_firmware() {
 
   # build .uf2 for nrf52 boards
   if [[ -f .pio/build/$1/firmware.zip && -f .pio/build/$1/firmware.hex ]]; then
-    python bin/uf2conv/uf2conv.py .pio/build/$1/firmware.hex -c -o .pio/build/$1/firmware.uf2 -f 0xADA52840
+    python3 bin/uf2conv/uf2conv.py .pio/build/$1/firmware.hex -c -o .pio/build/$1/firmware.uf2 -f 0xADA52840
   fi
 
   # copy .bin, .uf2, and .zip to out folder